Six high school girls are involved in initiation ceremonies for their exclusive society, The Sisters. A shot from a presumably harmless pistol, part of the ritual, kills Liz (Elizabeth Bergen).

Seven years later each of the remaining Sisters receive identical letters inviting them to a reunion in isolated estate mansion.
With nightfall the reign of terror and madness begins as Liz's death is revenged.

Two nights before Halloween, as if it matters to anyone in the house, as if every day in this house isn’t Halloween. As if every moment they live isn’t the strain and stretch, the hand reaching back, groping through bottomless candy bags down to where front porches glowing with orange flicker grins and skeletons dance hopscotch sidewalks and ring doorbells. And they are all here, here around where they belong.
From Silk By Caitlin R. Kiernan